Dienstag, 9. Oktober 2012

Bug in BlinkM

You should be able to just change the hfuse and that's it. I tend to do everything ("nuke it from orbit, it's the only way to be sure") :-)To make adjust the BOD-level by just changing the lfuse, the avrdude line becomes: avrdude -P usb -c avrispmkII -p attinyXX -v -U hfuse:w:0xDD:mThat sets the BOD to 2.7V. I think for BlinkM going any lower wouldn't be of much use since the lowest voltage the Red LED in BlinkM needs to turn on is around 2.5V (the Blue and Green need around 3.4V & 3.0V respectively) BlinkMs are designed to run at 5V (i.e. the colors are most balanced around that voltage)The way the BOD works is you want it's detection level to be as high as possible so it triggers (and thus puts the chip in reset) as soon as the chip's power source gets too low. In theory, having no BOD enabled is fine, but as we're seeing with the current run of these ATtiny chips, we want to put the chip in reset as soon as possible to avoid the EEPROM getting scrambled.